gcc/c-tree.h

   1 /* Definitions for C parsing and type checking.
   2    Copyright (C) 1987, 1993, 1994, 1995, 1997, 1998,
   3    1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22 #ifndef GCC_C_TREE_H
  23 #define GCC_C_TREE_H
  24
  25 #include "c-common.h"
  26 #include "diagnostic.h"
  27
  28 /* struct lang_identifier is private to c-decl.c, but langhooks.c needs to
  29    know how big it is.  This is sanity-checked in c-decl.c.  */
  30 #define C_SIZEOF_STRUCT_LANG_IDENTIFIER \
  31   (sizeof (struct c_common_identifier) + 3 * sizeof (void *))
  32
  33 /* For gc purposes, return the most likely link for the longest chain.  */
  34 #define C_LANG_TREE_NODE_CHAIN_NEXT(T)                          \
  35   ((union lang_tree_node *)                                     \
  36    (TREE_CODE (T) == INTEGER_TYPE ? TYPE_NEXT_VARIANT (T)       \
  37     : TREE_CODE (T) == COMPOUND_EXPR ? TREE_OPERAND (T, 1)      \
  38     : TREE_CHAIN (T)))
  39
  40 /* Language-specific declaration information.  */
  41
  42 struct lang_decl GTY(())
  43 {
  44   /* The return types and parameter types may have variable size.
  45      This is a list of any SAVE_EXPRs that need to be evaluated to
  46      compute those sizes.  */
  47   tree pending_sizes;
  48 };
  49
  50 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is read-only.  */
  51 #define C_TYPE_FIELDS_READONLY(TYPE) TREE_LANG_FLAG_1 (TYPE)
  52
  53 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is volatile.  */
  54 #define C_TYPE_FIELDS_VOLATILE(TYPE) TREE_LANG_FLAG_2 (TYPE)
  55
  56 /* In a RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE
  57    nonzero if the definition of the type has already started.  */
  58 #define C_TYPE_BEING_DEFINED(TYPE) TYPE_LANG_FLAG_0 (TYPE)
  59
  60 /* In an incomplete RECORD_TYPE or UNION_TYPE, a list of variable
  61    declarations whose type would be completed by completing that type.  */
  62 #define C_TYPE_INCOMPLETE_VARS(TYPE) TYPE_VFIELD (TYPE)
  63
  64 /* In an IDENTIFIER_NODE, nonzero if this identifier is actually a
  65    keyword.  C_RID_CODE (node) is then the RID_* value of the keyword,
  66    and C_RID_YYCODE is the token number wanted by Yacc.  */
  67 #define C_IS_RESERVED_WORD(ID) TREE_LANG_FLAG_0 (ID)
  68
  69 struct lang_type GTY(())
  70 {
  71   /* In a RECORD_TYPE, a sorted array of the fields of the type.  */
  72   struct sorted_fields_type * GTY ((reorder ("resort_sorted_fields"))) s;
  73   /* In an ENUMERAL_TYPE, the min and max values.  */
  74   tree enum_min;
  75   tree enum_max;
  76 };
  77
  78 /* Record whether a type or decl was written with nonconstant size.
  79    Note that TYPE_SIZE may have simplified to a constant.  */
  80 #define C_TYPE_VARIABLE_SIZE(TYPE) TYPE_LANG_FLAG_1 (TYPE)
  81 #define C_DECL_VARIABLE_SIZE(TYPE) DECL_LANG_FLAG_0 (TYPE)
  82
  83 /* Record whether a typedef for type `int' was actually `signed int'.  */
  84 #define C_TYPEDEF_EXPLICITLY_SIGNED(EXP) DECL_LANG_FLAG_1 (EXP)
  85
  86 /* For a FUNCTION_DECL, nonzero if it was defined without an explicit
  87    return type.  */
  88 #define C_FUNCTION_IMPLICIT_INT(EXP) DECL_LANG_FLAG_1 (EXP)
  89
  90 /* For a FUNCTION_DECL, nonzero if it was an implicit declaration.  */
  91 #define C_DECL_IMPLICIT(EXP) DECL_LANG_FLAG_2 (EXP)
  92
  93 /* For FUNCTION_DECLs, evaluates true if the decl is built-in but has
  94    been declared.  */
  95 #define C_DECL_DECLARED_BUILTIN(EXP) DECL_LANG_FLAG_3 (EXP)
  96
  97 /* Record whether a decl was declared register.  This is strictly a
  98    front-end flag, whereas DECL_REGISTER is used for code generation;
  99    they may differ for structures with volatile fields.  */
 100 #define C_DECL_REGISTER(EXP) DECL_LANG_FLAG_4 (EXP)
 101
 102 /* Record whether a decl was used in an expression anywhere except an
 103    unevaluated operand of sizeof / typeof / alignof.  This is only
 104    used for functions declared static but not defined, though outside
 105    sizeof and typeof it is set for other function decls as well.  */
 106 #define C_DECL_USED(EXP) DECL_LANG_FLAG_5 (EXP)
 107
 108 /* Nonzero for a decl which either doesn't exist or isn't a prototype.
 109    N.B. Could be simplified if all built-in decls had complete prototypes
 110    (but this is presently difficult because some of them need FILE*).  */
 111 #define C_DECL_ISNT_PROTOTYPE(EXP)                      \
 112        (EXP == 0                                        \
 113         || (TYPE_ARG_TYPES (TREE_TYPE (EXP)) == 0       \
 114             && !DECL_BUILT_IN (EXP)))
 115
 116 /* For FUNCTION_TYPE, a hidden list of types of arguments.  The same as
 117    TYPE_ARG_TYPES for functions with prototypes, but created for functions
 118    without prototypes.  */
 119 #define TYPE_ACTUAL_ARG_TYPES(NODE) TYPE_LANG_SLOT_1 (NODE)
 120
 121 /* Record parser information about an expression that is irrelevant
 122    for code generation alongside a tree representing its value.  */
 123 struct c_expr
 124 {
 125   /* The value of the expression.  */
 126   tree value;
 127   /* Record the original binary operator of an expression, which may
 128      have been changed by fold, STRING_CST for unparenthesised string
 129      constants, or ERROR_MARK for other expressions (including
 130      parenthesized expressions).  */
 131   enum tree_code original_code;
 132 };
 133
 134 /* A sequence of declaration specifiers in C.  */
 135 struct c_declspecs {
 136   /* The type specified, not reflecting modifiers such as "short" and
 137      "unsigned", or NULL_TREE if none.  */
 138   tree type;
 139   /* The attributes from a typedef decl.  */
 140   tree decl_attr;
 141   /* When parsing, the attributes.  Outside the parser, this will be
 142      NULL; attributes (possibly from multiple lists) will be passed
 143      separately.  */
 144   tree attrs;
 145   /* The modifier bits present.  */
 146   int specbits;
 147   /* Whether something other than a storage class specifier or
 148      attribute has been seen.  This is used to warn for the
 149      obsolescent usage of storage class specifiers other than at the
 150      start of the list.  (Doing this properly would require function
 151      specifiers to be handled separately from storage class
 152      specifiers.)  */
 153   BOOL_BITFIELD non_sc_seen_p : 1;
 154   /* Whether the type is specified by a typedef.  */
 155   BOOL_BITFIELD typedef_p : 1;
 156   /* Whether the type is specified by a typedef whose type is
 157      explicitly "signed".  */
 158   BOOL_BITFIELD typedef_signed_p : 1;
 159   /* Whether the specifiers include a deprecated typedef.  */
 160   BOOL_BITFIELD deprecated_p : 1;
 161   /* Whether "int" was explicitly specified.  */
 162   BOOL_BITFIELD explicit_int_p : 1;
 163   /* Whether "char" was explicitly specified.  */
 164   BOOL_BITFIELD explicit_char_p : 1;
 165   /* Whether "long" was specified more than once.  */
 166   BOOL_BITFIELD long_long_p : 1;
 167 };
 168
 169 /* The various kinds of declarators in C.  */
 170 enum c_declarator_kind {
 171   /* An identifier.  */
 172   cdk_id,
 173   /* A function.  */
 174   cdk_function,
 175   /* An array.  */
 176   cdk_array,
 177   /* A pointer.  */
 178   cdk_pointer,
 179   /* Parenthesized declarator with nested attributes.  */
 180   cdk_attrs
 181 };
 182
 183 /* Information about the parameters in a function declarator.  */
 184 struct c_arg_info {
 185   /* A list of parameter decls.  */
 186   tree parms;
 187   /* A list of structure, union and enum tags defined.  */
 188   tree tags;
 189   /* A list of argument types to go in the FUNCTION_TYPE.  */
 190   tree types;
 191   /* A list of non-parameter decls (notably enumeration constants)
 192      defined with the parameters.  */
 193   tree others;
 194 };
 195
 196 /* A declarator.  */
 197 struct c_declarator {
 198   /* The kind of declarator.  */
 199   enum c_declarator_kind kind;
 200   /* Except for cdk_id, the contained declarator.  For cdk_id, NULL.  */
 201   struct c_declarator *declarator;
 202   union {
 203     /* For identifiers, an IDENTIFIER_NODE or NULL_TREE if an abstract
 204        declarator.  */
 205     tree id;
 206     /* For functions.  */
 207     struct c_arg_info *arg_info;
 208     /* For arrays.  */
 209     struct {
 210       /* The array dimension, or NULL for [] and [*].  */
 211       tree dimen;
 212       /* The qualifiers (and attributes, currently ignored) inside [].  */
 213       struct c_declspecs *quals;
 214       /* Whether [static] was used.  */
 215       BOOL_BITFIELD static_p : 1;
 216       /* Whether [*] was used.  */
 217       BOOL_BITFIELD vla_unspec_p : 1;
 218     } array;
 219     /* For pointers, the qualifiers on the pointer type.  */
 220     struct c_declspecs *pointer_quals;
 221     /* For attributes.  */
 222     tree attrs;
 223   } u;
 224 };
 225
 226 /* A type name.  */
 227 struct c_type_name {
 228   /* The declaration specifiers.  */
 229   struct c_declspecs *specs;
 230   /* The declarator.  */
 231   struct c_declarator *declarator;
 232 };
 233
 234 /* A parameter.  */
 235 struct c_parm {
 236   /* The declaration specifiers, minus any prefix attributes.  */
 237   struct c_declspecs *specs;
 238   /* The attributes.  */
 239   tree attrs;
 240   /* The declarator.  */
 241   struct c_declarator *declarator;
 242 };
 243
 244 /* Save and restore the variables in this file and elsewhere
 245    that keep track of the progress of compilation of the current function.
 246    Used for nested functions.  */
 247
 248 struct language_function GTY(())
 249 {
 250   struct c_language_function base;
 251   tree x_break_label;
 252   tree x_cont_label;
 253   struct c_switch * GTY((skip)) x_switch_stack;
 254   struct c_arg_info * GTY((skip)) arg_info;
 255   int returns_value;
 256   int returns_null;
 257   int returns_abnormally;
 258   int warn_about_return_type;
 259   int extern_inline;
 260 };
 261
 262 \f
 263 /* in c-parse.in */
 264 extern void c_parse_init (void);
 265
 266 /* in c-aux-info.c */
 267 extern void gen_aux_info_record (tree, int, int, int);
 268
 269 /* in c-decl.c */
 270 extern struct obstack parser_obstack;
 271 extern tree c_break_label;
 272 extern tree c_cont_label;
 273
 274 extern int global_bindings_p (void);
 275 extern void push_scope (void);
 276 extern tree pop_scope (void);
 277 extern void insert_block (tree);
 278 extern tree pushdecl (tree);
 279 extern void c_expand_body (tree);
 280
 281 extern void c_init_decl_processing (void);
 282 extern void c_dup_lang_specific_decl (tree);
 283 extern void c_print_identifier (FILE *, tree, int);
 284 extern struct c_declarator *build_array_declarator (tree, struct c_declspecs *,
 285                                                     bool, bool);
 286 extern tree build_enumerator (tree, tree);
 287 extern void check_for_loop_decls (void);
 288 extern void mark_forward_parm_decls (void);
 289 extern int  complete_array_type (tree, tree, int);
 290 extern void declare_parm_level (void);
 291 extern void undeclared_variable (tree);
 292 extern tree declare_label (tree);
 293 extern tree define_label (location_t, tree);
 294 extern void finish_decl (tree, tree, tree);
 295 extern tree finish_enum (tree, tree, tree);
 296 extern void finish_function (void);
 297 extern tree finish_struct (tree, tree, tree);
 298 extern struct c_arg_info *get_parm_info (bool);
 299 extern tree grokfield (struct c_declarator *, struct c_declspecs *, tree);
 300 extern tree groktypename (struct c_type_name *);
 301 extern tree grokparm (const struct c_parm *);
 302 extern tree implicitly_declare (tree);
 303 extern void keep_next_level (void);
 304 extern tree lookup_name (tree);
 305 extern void pending_xref_error (void);
 306 extern void c_push_function_context (struct function *);
 307 extern void c_pop_function_context (struct function *);
 308 extern void push_parm_decl (const struct c_parm *);
 309 extern tree pushdecl_top_level (tree);
 310 extern struct c_declarator *set_array_declarator_inner (struct c_declarator *,
 311                                                         struct c_declarator *,
 312                                                         bool);
 313 extern tree builtin_function (const char *, tree, int, enum built_in_class,
 314                               const char *, tree);
 315 extern void shadow_tag (const struct c_declspecs *);
 316 extern void shadow_tag_warned (const struct c_declspecs *, int);
 317 extern tree start_enum (tree);
 318 extern int  start_function (struct c_declspecs *, struct c_declarator *, tree);
 319 extern tree start_decl (struct c_declarator *, struct c_declspecs *, bool,
 320                         tree);
 321 extern tree start_struct (enum tree_code, tree);
 322 extern void store_parm_decls (void);
 323 extern void store_parm_decls_from (struct c_arg_info *);
 324 extern tree xref_tag (enum tree_code, tree);
 325 extern int c_expand_decl (tree);
 326 extern struct c_parm *build_c_parm (struct c_declspecs *, tree,
 327                                     struct c_declarator *);
 328 extern struct c_declarator *build_attrs_declarator (tree,
 329                                                     struct c_declarator *);
 330 extern struct c_declarator *build_function_declarator (struct c_arg_info *,
 331                                                        struct c_declarator *);
 332 extern struct c_declarator *build_id_declarator (tree);
 333 extern struct c_declarator *make_pointer_declarator (struct c_declspecs *,
 334                                                      struct c_declarator *);
 335 extern struct c_declspecs *build_null_declspecs (void);
 336 extern struct c_declspecs *declspecs_add_qual (struct c_declspecs *, tree);
 337 extern struct c_declspecs *declspecs_add_type (struct c_declspecs *, tree);
 338 extern struct c_declspecs *declspecs_add_scspec (struct c_declspecs *, tree);
 339 extern struct c_declspecs *declspecs_add_attrs (struct c_declspecs *, tree);
 340
 341 /* in c-objc-common.c */
 342 extern int c_disregard_inline_limits (tree);
 343 extern int c_cannot_inline_tree_fn (tree *);
 344 extern bool c_objc_common_init (void);
 345 extern bool c_missing_noreturn_ok_p (tree);
 346 extern tree c_objc_common_truthvalue_conversion (tree expr);
 347 extern int defer_fn (tree);
 348 extern bool c_warn_unused_global_decl (tree);
 349 extern void c_initialize_diagnostics (diagnostic_context *);
 350
 351 #define c_build_type_variant(TYPE, CONST_P, VOLATILE_P)           \
 352   c_build_qualified_type ((TYPE),                                 \
 353                           ((CONST_P) ? TYPE_QUAL_CONST : 0) |     \
 354                           ((VOLATILE_P) ? TYPE_QUAL_VOLATILE : 0))
 355
 356 /* in c-typeck.c */
 357 extern int in_alignof;
 358 extern int in_sizeof;
 359 extern int in_typeof;
 360
 361 extern struct c_switch *c_switch_stack;
 362
 363 extern tree require_complete_type (tree);
 364 extern int same_translation_unit_p (tree, tree);
 365 extern int comptypes (tree, tree);
 366 extern tree c_size_in_bytes (tree);
 367 extern bool c_mark_addressable (tree);
 368 extern void c_incomplete_type_error (tree, tree);
 369 extern tree c_type_promotes_to (tree);
 370 extern tree composite_type (tree, tree);
 371 extern tree build_component_ref (tree, tree);
 372 extern tree build_indirect_ref (tree, const char *);
 373 extern tree build_array_ref (tree, tree);
 374 extern tree build_external_ref (tree, int);
 375 extern void record_maybe_used_decl (tree);
 376 extern void pop_maybe_used (bool);
 377 extern struct c_expr c_expr_sizeof_expr (struct c_expr);
 378 extern struct c_expr c_expr_sizeof_type (struct c_type_name *);
 379 extern struct c_expr parser_build_binary_op (enum tree_code, struct c_expr,
 380                                              struct c_expr);
 381 extern void readonly_error (tree, const char *);
 382 extern tree build_conditional_expr (tree, tree, tree);
 383 extern tree build_compound_expr (tree, tree);
 384 extern tree c_cast_expr (struct c_type_name *, tree);
 385 extern tree build_c_cast (tree, tree);
 386 extern tree build_modify_expr (tree, enum tree_code, tree);
 387 extern void store_init_value (tree, tree);
 388 extern void error_init (const char *);
 389 extern void pedwarn_init (const char *);
 390 extern void maybe_warn_string_init (tree, struct c_expr);
 391 extern void start_init (tree, tree, int);
 392 extern void finish_init (void);
 393 extern void really_start_incremental_init (tree);
 394 extern void push_init_level (int);
 395 extern struct c_expr pop_init_level (int);
 396 extern void set_init_index (tree, tree);
 397 extern void set_init_label (tree);
 398 extern void process_init_element (struct c_expr);
 399 extern tree build_compound_literal (tree, tree);
 400 extern void pedwarn_c90 (const char *, ...) ATTRIBUTE_PRINTF_1;
 401 extern void pedwarn_c99 (const char *, ...) ATTRIBUTE_PRINTF_1;
 402 extern tree c_start_case (tree);
 403 extern void c_finish_case (tree);
 404 extern tree build_asm_expr (tree, tree, tree, tree, bool);
 405 extern tree build_asm_stmt (tree, tree);
 406 extern tree c_convert_parm_for_inlining (tree, tree, tree, int);
 407 extern int c_types_compatible_p (tree, tree);
 408 extern tree c_begin_compound_stmt (bool);
 409 extern tree c_end_compound_stmt (tree, bool);
 410 extern void c_finish_if_stmt (location_t, tree, tree, tree, bool);
 411 extern void c_finish_loop (location_t, tree, tree, tree, tree, tree, bool);
 412 extern tree c_begin_stmt_expr (void);
 413 extern tree c_finish_stmt_expr (tree);
 414 extern tree c_process_expr_stmt (tree);
 415 extern tree c_finish_expr_stmt (tree);
 416 extern tree c_finish_return (tree);
 417 extern tree c_finish_bc_stmt (tree *, bool);
 418 extern tree c_finish_goto_label (tree);
 419 extern tree c_finish_goto_ptr (tree);
 420
 421 /* Set to 0 at beginning of a function definition, set to 1 if
 422    a return statement that specifies a return value is seen.  */
 423
 424 extern int current_function_returns_value;
 425
 426 /* Set to 0 at beginning of a function definition, set to 1 if
 427    a return statement with no argument is seen.  */
 428
 429 extern int current_function_returns_null;
 430
 431 /* Set to 0 at beginning of a function definition, set to 1 if
 432    a call to a noreturn function is seen.  */
 433
 434 extern int current_function_returns_abnormally;
 435
 436 /* Nonzero means we are reading code that came from a system header file.  */
 437
 438 extern int system_header_p;
 439
 440 /* True means global_bindings_p should return false even if the scope stack
 441    says we are in file scope.  */
 442
 443 extern bool c_override_global_bindings_to_false;
 444
 445 /* True means we've initialized exception handling.  */
 446 extern bool c_eh_initialized_p;
 447
 448 /* In c-decl.c */
 449 extern void c_finish_incomplete_decl (tree);
 450 extern void c_write_global_declarations (void);
 451
 452 /* In order for the format checking to accept the C frontend
 453    diagnostic framework extensions, you must include this file before
 454    toplev.h, not after.  */
 455 #define GCC_DIAG_STYLE __gcc_cdiag__
 456
 457 #endif /* ! GCC_C_TREE_H */